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This iD Mobile SIM gets you 40GB for just £4

If you already have a handset, a SIM-only contract is a great way to get your mobile service on the cheap.

Mobiles UK is offering a 40GB monthly SIM and data for just £4 a month after cash back is calculated.

40GB SIM-only contract for £4 a month. Not a typo.

40GB SIM-only contract for £4 a month. Not a typo.

The iD Mobile network offers some shockingly great deals, but this 40GB contract with 50% cashback might be the best we’ve seen.


  • Mobiles UK
  • 50% cash back
  • £4 a month
View Deal

You will be billed £8 a month but you can claim £96 back by sensing in your mobile bill every few months to receive five payments of £19.20. All the details you need about claiming the cashback are here.

It’s a 24-month contract that also comes with unlimited texts and minutes and it’s on the iD Mobile network.

If you’re unfamiliar with iD, it’s an MVNO – a mobile virtual network operator. That means it runs off the mobile spectrum of an existing network. iD uses Three Mobile’s infrastructure, so you can expect the same level of service, 5G data speeds and more.

Because the MVNO doesn’t have to pay to maintain the physical networks and simply leases them from the providers, they’re able to pass savings on to consumers.

You may lose out on some of the customer service perks you get from the big networks, but that’s not the end of the world when you’re getting 40GB of data for £4 a month.

MVNOs had a less than stellar reputation in the past, but they’re no longer the poor cousins of the big networks. There’s good 5G performance and free roaming in the EU, which is a huge bonus in the post-Brexit world. The network also locks in the price for the entire length of your contract, so no annual price hikes for inflation.

iD Mobile has a four star rating from 25,000 reviews on TrustPilot, so that should reassure you too.

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